# AGENTS.md — Python (PEP 8)

- Indent with **4 spaces**, never tabs. No trailing whitespace.
- Keep lines to **79 chars** (72 for comments/docstrings); up to 99 only by team agreement.
- **Two blank lines** between top-level defs/classes; **one** between methods.
- `snake_case` for functions/variables/methods/modules; `CapWords` for classes (exceptions end in `Error`); `UPPER_CASE` for constants.
- `_leading_underscore` = non-public. Never use `l`, `O`, or `I` as names. First args are `self` / `cls`.
- One import per line; group **stdlib / third-party / local** with a blank line between; no wildcard imports.
- No spaces inside `()[]{}` or before `,;:`; single spaces around binary operators; no spaces around `=` in kwargs unless the param is annotated.
- Break long lines **before** the operator.
- Docstrings (`"""..."""`) on every public module/class/function/method; imperative mood, period; closing `"""` on its own line for multi-line.
- Compare to `None` with `is`/`is not`; use `isinstance(...)`; rely on truthiness (`if not seq:`).
- No bare `except:`; catch specific exceptions, keep `try` blocks small.
- Use `def`, not a lambda bound to a name.
- Type hints (`x: int -> str`) are optional and static-only; use `Optional[T]` / `T | None`.
- Run `ruff` / `black` to enforce layout — PEP 8 values readability and module-level consistency over rigid rule-following.